Title :
A simple pre-filtering for spectral smoothing in a radio frequency digital to analog converter
Author :
Rahmatollahi, Shoeib ; Jannesari, Abumoslem
Author_Institution :
ECE Dept., Tarbiat-Modares Univ., Tehran, Iran
Abstract :
A new pre-filtering scheme for direct digital to RF converter is presented. The converter consists of a 400MS/s digital ΣΔ modulator followed by a 2.4-GHz digital to Radio Frequency (RF) converter. The proposed structure attenuates the out-of-band spectral and relaxes the design of ΣΔ and RF-Filter. The technique is based on using First Order Hold filter in respect to use the conventional Zero Order Hold filter. The simulation result shows 16dB image rejection improvement. Also, the modulator achieved 79dB of Signal to Noise Ratio in 5MHz of band width. The output power is -4dBm while power consumption is about 2.55mW.
Keywords :
digital-analogue conversion; modulators; power consumption; radiofrequency filters; spectral analysis; RF-filter; bandwidth 5 MHz; digital ΣΔ modulator; digital to radio frequency converter; direct digital to RF converter; first order hold filter; frequency 2.4 GHz; image rejection improvement; out-of-band spectral; power consumption; prefiltering scheme; radio frequency digital to analog converter; signal to noise ratio; spectral smoothing; zero order hold filter; Mixers; Modulation; Radio frequency; Resonator filters; Signal to noise ratio; Delta-Sigma-Modulator(DSM); First-Order-Hold (FOH); Intersymbol Interference (ISI); Radio Frequency Digital to Analog Converter (RFDAC);
Conference_Titel :
Circuits and Systems (ICCAS), 2012 IEEE International Conference on
Conference_Location :
Kuala Lumpur
Print_ISBN :
978-1-4673-3117-3
Electronic_ISBN :
978-1-4673-3118-0
DOI :
10.1109/ICCircuitsAndSystems.2012.6408313
